// Global variables
let videos = [];
let currentVideoId = null;
let currentPage = 1;
const videosPerPage = 12;
let filteredVideos = [];

// DOM elements
const videoGrid = document.getElementById('videoGrid');
const suggestionsContainer = document.getElementById('suggestions');
const videoTitle = document.getElementById('videoTitle');
const videoDescription = document.getElementById('videoDescription');
const searchInput = document.getElementById('searchInput');
const searchBtn = document.getElementById('searchBtn');
const paginationContainer = document.getElementById('pagination');

// Initialize the app based on current page
document.addEventListener('DOMContentLoaded', () => {
    loadVideos();
    
    if (window.location.pathname.includes('player.html')) {
        initPlayer();
    } else {
        // Setup search functionality for index page
        searchInput.addEventListener('input', handleSearch);
        searchBtn.addEventListener('click', handleSearch);
    }
});

// Load videos from database.json
async function loadVideos() {
    try {
        const response = await fetch('database.json');
        videos = await response.json();
        filteredVideos = [...videos];
        
        if (window.location.pathname.includes('player.html')) {
            // Player page - load current video and suggestions
            const urlParams = new URLSearchParams(window.location.search);
            currentVideoId = urlParams.get('v');
            
            if (currentVideoId) {
                loadVideo(currentVideoId);
                renderSuggestions();
            } else {
                // Redirect to home if no video specified
                window.location.href = 'index.html';
            }
        } else {
            // Home page - render video grid
            renderVideoGrid();
            renderPagination();
        }
    } catch (error) {
        console.error('Error loading videos:', error);
        alert('Failed to load video data. Please try again later.');
    }
}

// Handle search functionality
function handleSearch() {
    const searchTerm = searchInput.value.toLowerCase();
    
    if (searchTerm.trim() === '') {
        filteredVideos = [...videos];
    } else {
        filteredVideos = videos.filter(video => 
            video.title.toLowerCase().includes(searchTerm) || 
            video.description.toLowerCase().includes(searchTerm)
        );
    }
    
    currentPage = 1;
    renderVideoGrid();
    renderPagination();
}

// Render video grid on home page with pagination
function renderVideoGrid() {
    if (!videoGrid) return;
    
    videoGrid.innerHTML = '';
    
    const startIndex = (currentPage - 1) * videosPerPage;
    const endIndex = startIndex + videosPerPage;
    const videosToShow = filteredVideos.slice(startIndex, endIndex);
    
    if (videosToShow.length === 0) {
        videoGrid.innerHTML = '<p class="no-results">No videos found matching your search.</p>';
        return;
    }
    
    videosToShow.forEach(video => {
        const videoCard = document.createElement('div');
        videoCard.className = 'video-card';
        videoCard.addEventListener('click', () => {
            window.location.href = `player.html?v=${video.id}`;
        });
        
        videoCard.innerHTML = `
            <div class="thumbnail">
                <img src="${video.thumbnailPath}" alt="${video.title}" loading="lazy">
                ${video.duration ? `<span class="duration">${video.duration}</span>` : ''}
            </div>
            <div class="video-info">
                <h3>${video.title}</h3>
                <p>${video.description.substring(0, 100)}...</p>
            </div>
        `;
        
        videoGrid.appendChild(videoCard);
    });
}

// Render pagination controls
function renderPagination() {
    if (!paginationContainer) return;
    
    paginationContainer.innerHTML = '';
    
    const totalPages = Math.ceil(filteredVideos.length / videosPerPage);
    
    if (totalPages <= 1) return;
    
    // Previous button
    const prevBtn = document.createElement('button');
    prevBtn.className = 'page-btn';
    prevBtn.textContent = 'Previous';
    prevBtn.disabled = currentPage === 1;
    prevBtn.addEventListener('click', () => {
        if (currentPage > 1) {
            currentPage--;
            renderVideoGrid();
            renderPagination();
            window.scrollTo({ top: 0, behavior: 'smooth' });
        }
    });
    paginationContainer.appendChild(prevBtn);
    
    // Page buttons
    const maxVisiblePages = 5;
    let startPage = Math.max(1, currentPage - Math.floor(maxVisiblePages / 2));
    let endPage = Math.min(totalPages, startPage + maxVisiblePages - 1);
    
    if (endPage - startPage + 1 < maxVisiblePages) {
        startPage = Math.max(1, endPage - maxVisiblePages + 1);
    }
    
    if (startPage > 1) {
        const firstBtn = document.createElement('button');
        firstBtn.className = 'page-btn';
        firstBtn.textContent = '1';
        firstBtn.addEventListener('click', () => {
            currentPage = 1;
            renderVideoGrid();
            renderPagination();
            window.scrollTo({ top: 0, behavior: 'smooth' });
        });
        paginationContainer.appendChild(firstBtn);
        
        if (startPage > 2) {
            const ellipsis = document.createElement('span');
            ellipsis.textContent = '...';
            paginationContainer.appendChild(ellipsis);
        }
    }
    
    for (let i = startPage; i <= endPage; i++) {
        const pageBtn = document.createElement('button');
        pageBtn.className = `page-btn ${i === currentPage ? 'active' : ''}`;
        pageBtn.textContent = i;
        pageBtn.addEventListener('click', () => {
            currentPage = i;
            renderVideoGrid();
            renderPagination();
            window.scrollTo({ top: 0, behavior: 'smooth' });
        });
        paginationContainer.appendChild(pageBtn);
    }
    
    if (endPage < totalPages) {
        if (endPage < totalPages - 1) {
            const ellipsis = document.createElement('span');
            ellipsis.textContent = '...';
            paginationContainer.appendChild(ellipsis);
        }
        
        const lastBtn = document.createElement('button');
        lastBtn.className = 'page-btn';
        lastBtn.textContent = totalPages;
        lastBtn.addEventListener('click', () => {
            currentPage = totalPages;
            renderVideoGrid();
            renderPagination();
            window.scrollTo({ top: 0, behavior: 'smooth' });
        });
        paginationContainer.appendChild(lastBtn);
    }
    
    // Next button
    const nextBtn = document.createElement('button');
    nextBtn.className = 'page-btn';
    nextBtn.textContent = 'Next';
    nextBtn.disabled = currentPage === totalPages;
    nextBtn.addEventListener('click', () => {
        if (currentPage < totalPages) {
            currentPage++;
            renderVideoGrid();
            renderPagination();
            window.scrollTo({ top: 0, behavior: 'smooth' });
        }
    });
    paginationContainer.appendChild(nextBtn);
}

// Load a specific video on player page
function loadVideo(videoId) {
    const video = videos.find(v => v.id === videoId);
    if (!video) {
        alert('Video not found');
        window.location.href = 'index.html';
        return;
    }
    
    currentVideoId = videoId;
    videoTitle.textContent = video.title;
    videoDescription.textContent = video.description;
    
    // Update page title
    document.title = `${video.title} - Video Browser`;
    
    // Initialize Video.js player
    const player = videojs('mainVideo', {
        controls: true,
        autoplay: false,
        preload: 'auto',
        responsive: true,
        fluid: true,
        sources: [{
            src: video.videoPath,
            type: 'video/mp4' // Adjust based on your video format
        }]
    });
    
    // Add subtitle tracks if available
    if (video.subtitleTracks) {
        video.subtitleTracks.forEach(track => {
            player.addRemoteTextTrack({
                kind: 'subtitles',
                src: track.path,
                srclang: track.srclang,
                label: track.label,
                default: track.srclang === 'en' // Default to English if available
            }, false);
        });
    }
    
    // Handle player errors
    player.on('error', () => {
        const errorDisplay = player.errorDisplay;
        errorDisplay.contentEl().innerHTML = `
            <div class="vjs-error-display">
                <div class="vjs-modal-dialog-content">
                    <h1>Error loading video</h1>
                    <p>The video format may not be supported by your browser.</p>
                    <p>Try using a different browser or check the video file.</p>
                </div>
            </div>
        `;
        errorDisplay.show();
    });
}

// Render suggested videos
function renderSuggestions() {
    if (!suggestionsContainer) return;
    
    // Filter out current video
    const suggestedVideos = videos.filter(v => v.id !== currentVideoId);
    
    suggestionsContainer.innerHTML = '<h2>Suggested Videos</h2>';
    
    suggestedVideos.forEach(video => {
        const suggestionCard = document.createElement('div');
        suggestionCard.className = 'suggestion-card';
        suggestionCard.addEventListener('click', () => {
            // Update URL without reloading the page
            window.history.pushState({}, '', `player.html?v=${video.id}`);
            loadVideo(video.id);
            renderSuggestions();
        });
        
        suggestionCard.innerHTML = `
            <div class="suggestion-thumbnail">
                <img src="${video.thumbnailPath}" alt="${video.title}" loading="lazy">
            </div>
            <div class="suggestion-info">
                <h3>${video.title}</h3>
                ${video.duration ? `<p>${video.duration}</p>` : ''}
            </div>
        `;
        
        suggestionsContainer.appendChild(suggestionCard);
    });
}

// Initialize video player (Video.js handles most of this now)
function initPlayer() {
    // Video.js is initialized in loadVideo function
}